As shown in FIG. 1, a doorbell of the prior art is generally composed of a cover, a chime bar, a base, a striker, and a resonator cover.
The prior art doorbell is not cost-effective in view of the fact that it is rather complicated in construction. For example, the base is made integrally and is provided with two hollow resonators which are provided respectively in a front wall there of and a rear wall thereof with a locating projection. The locating projection is provided at the top thereof with a diminishing neck portion, which is attached securely to the bottom of the hollow resonators located at both sides of the base. Located between the two resonators are two locating slots. The base is provided by punching with a through hole located between the two locating slots.
The structural complexity of the prior art doorbell is further evident by the fact that the striker of the prior art doorbell is rather complicated in construction. For example, the striker comprises a hollow member fitted in to a coil. The hollow member is provided respectively at the front end thereof and the rear end thereof with a short tube edge, which is retained in a locating through hole of a U-shaped body. A striking bar is first fitted into a spring before it is disposed in the hollow interior of the striker. The U-shaped body is provided respectively by punching at the bottoms of the front and the rear sides thereof with a protruded portion engageable with the locating slot. The U-shaped body is further provided at the lower end thereof with two legs, which are located in the through holes located between two frame edges. The U-shaped body is still further provided at the top end thereof with two legs, which are located in the through holes of a flat plate on which a fastening piece of the power source wire is fastened by means of screws. The coil of the striker is connected with the fastening piece of the power source wire.
It must be not here that the rejection rate of the prior art doorbell described above is relatively high, and that the U-shaped body, the striker and the base of the prior art doorbell described above can not be fastened securely.